The present invention relates to a sticking device for sticking a double-coated adhesive tape piece, which is used to connect webs, to one of the webs.
In a cigarette manufacturing machine, cut tobacco is wrapped up in a paper that is supplied from a paper supply device, whereby a cigarette rod is formed. Accordingly, the paper must be supplied continuously lest this wrapping operation be interrupted. Normally, therefore, the paper supply device is furnished with two reels such that, when the working paper remaining on one reel is scarce, a new paper delivered from the other can be connected to the working paper. Generally, in this paper connection, the leading end of the new paper and the trailing end of the working paper are connected by means of a double-coated adhesive tape piece that is previously stuck to the leading end of the new paper.
In the manufacture of filter cigarettes in which filters attached to cigarettes by means of tip papers, the tip papers may be connected to one another by means of double-coated adhesive tape pieces to facilitate continuous supply of the tip papers, in some cases.
Conventionally, a device described in Jpn. Pat. Appln. KOKAI Publication No. 9-40270 is used to stick double-coated adhesive tape pieces to webs, such as papers, tip papers, etc. This adhesive tape supply device comprises a guide mechanism for guiding an adhesive tape band (hereinafter referred to as tape band) so that one of double-coated adhesive tape pieces on a mount of the tape band faces a web, and a push mechanism for moving a push member opposed to the web toward the web. The double-coated adhesive tape piece is pressed against the web to be stuck to it by means of the push member.
According to this adhesive tape supply device, the entire tape piece is pressed against the web by means of the push member in sticking the tape piece to the web, so that the possibility of the web being dislocated from a given position or wrinkled is lowered. Thus, the aforesaid adhesive tape supply device has an advantage in being able to stick tape pieces to highly flexible thin webs, such as papers, tip papers.
In sticking a double-coated adhesive tape piece of an adhesive tape band to a highly flexible thin web by means of this adhesive tape supply device, however, the adhesive tape band sometimes cannot be smoothly separated from the web after the tape piece is stuck. In this case, the web cannot be transported from a tape piece sticking position to a web connecting position, so that continuous supply of the web is retarded.
The object of the present invention is to provide a sticking device capable of securely sticking one of double-coated adhesive tape pieces on a mount of an adhesive tape band to a web and securely separating the adhesive tape band from the web.
In order to achieve the above object, according to the present invention, there is provided an adhesive tape piece sticking device that sticks a double-coated adhesive tape piece to a web in a web path section defined by a guide element and constituting a part of a web path.
The adhesive tape piece sticking device according to the present invention comprises: a delivery section for delivering an adhesive tape band composed of a mount and a plurality of double-coated adhesive tape pieces provided thereon; a guide section including first and second guide units arranged for relative movement toward and away from each other along the web path section and for relative movement relative to the guide element in a direction across the web path section, said first and second guide units serving to guide the adhesive tape band from the mount side thereof and form a projecting region with a variable region length in an adhesive tape band path, said projecting region projecting toward the web path section in the direction across the web path section, extending along the web path section, and permitting one of the double-coated adhesive tape pieces to be positioned in said projecting region; a first drive section for relatively moving the first and second guide units and the guide element toward and away from one another in the direction across the web path section; and a second drive section for relatively moving the first and second guide units toward and away from each other along the web path section.
According to the sticking device of the present invention, the first and second guide units of the guide section form the projecting region in the adhesive tape band path, and adhesive tape band runs as the delivery section is driven. The drive of the delivery section is stopped if, for example, the outermost one (on the lowest-stream side) of the double-coated adhesive tape pieces on the mount of the adhesive tape band is situated in the projecting region. Then, the first drive section is actuated so that the first and second guide units and the guide element relatively move toward one another in the direction across the web path section, and the double-coated adhesive tape piece that is situated in the projecting region is brought entire into contact with the web that stands still in the web path section, whereupon the double-coated adhesive tape piece is stuck to the web. Subsequently, the second drive section is actuated so that the first and second guide units relatively move toward each other along the web path section. As the two guide units move toward each other, the projecting region is shortened in length, so that the portion of the mount of the adhesive tape band having so far been in the projecting region is driven out of the projecting region. Thus, this mount portion moves away from the web path section in the direction across the web path section, so that it is separated from the double-coated adhesive tape piece that is stuck to the web. In sticking one of the double-coated adhesive tape pieces to the web, in this manner, the double-coated adhesive tape piece and the mount can be separated from each other securely and smoothly.
Preferably, according to the present invention, the guide section includes a guide section body movable toward and away from the guide element in the direction across the web path section. The second guide unit is fixed to the guide section body, and the first guide unit is supported on the guide section body for movement relative to the guide section body along the web path section. The first drive section moves the guide section body toward and away from the guide element in the direction across the web path section, and the second drive section moves the first guide unit toward and away from the guide section body along the web path section.
According to this preferred mode, the configurations of individual parts of the sticking device that are associated with the relative movement of the first and second guide units and the relative movement of the two guide units and the guide element and the drive control sequence therefor are simplified.
Further preferably, the guide section includes a first guide roller located on the upstream side of the projecting region in the adhesive tape band path and rotatably supported on the guide section body in a position opposite from the web path section with respect to the projecting region in the direction across the web path section, a base block supported on the guide section body for movement relative to the guide section body along the web path section, and a second guide roller located on the downstream side of the projecting region in the adhesive tape band path and rotatably supported on the base block in a position opposite from the web path section with respect to the projecting region in the direction across the web path section.
According to this preferred mode, the projecting region can be securely formed in the adhesive tape band path, and the travel of the adhesive tape band from the upstream side of the projecting region to the same region and the travel of the adhesive tape band from the projecting region to the downstream side thereof can be carried out smoothly.
Preferably, the plurality of double-coated adhesive tape pieces are stuck to the mount beforehand at spaces from one another in the longitudinal direction of the adhesive tape band.
According to this preferred mode, a plurality of double-coated adhesive tape pieces can be arranged on the mount without providing the sticking device with any cutting section for cutting the continuous double-coated adhesive tape, which are previously stuck to the mount, into the aforesaid plurality of double-coated adhesive tape pieces, so that the construction of the sticking device is simple. Since the given spaces are secured between the double-coated adhesive tape pieces, moreover, one double-coated adhesive tape piece can be securely positioned in the projecting region of the adhesive tape band path, this double-coated adhesive tape piece can be stuck to the web with reliability, and this double-coated adhesive tape piece and the mount can be securely separated from each other.
Preferably, the sticking device of the present invention further comprises a detection unit, located opposite the adhesive tape band path, for outputting a detection signal indicative of the running position of the adhesive tape band in the adhesive tape band path, and an adjusting unit for adjusting the delivery of the adhesive tape band by means of the delivery section in accordance with the detection signal.
According to this preferred mode, the delivery of the adhesive tape band is adjusted in accordance with the running position of the adhesive tape band, so that one double-coated adhesive tape piece can be accurately positioned in the projecting region of the adhesive tape band path.
Further preferably, the plurality of double-coated adhesive tape pieces have a color different from that of the mount. The detection unit includes at least one optical sensor located opposite the adhesive tape band path.
According to this preferred mode, the double-coated adhesive tape pieces have a color different from that of the mount, so that boundary portions between the double-coated adhesive tape pieces and the mount (no-tape-piece portion or mount-exposing portion of the adhesive tape band) can be clearly discriminated in an optical manner. Accordingly, the running position of the adhesive tape band can be optically detected with high accuracy by means of the optical sensor. It is unnecessary, moreover, to provide any special optical position marks between the double-coated adhesive tape pieces, so that the configuration of the adhesive tape band is simple.
Preferably, the sticking device of the present invention further comprises a movement restraining unit for temporarily restraining the movement of the adhesive tape band along the adhesive tape band path.
According to this preferred mode, a substantial tension can be applied to the adhesive tape band by temporarily restraining the movement or travel of the adhesive tape band in sticking the double-coated adhesive tape piece situated in the projecting region of the adhesive tape band to the web and in separating the double-coated adhesive tape piece and the mount from each other, so that sticking of the tape piece to the web and separation of the tape piece and the mount can be carried out securely.
Preferably, the sticking device of the present invention further comprises a brake mechanism including a brake drum rotatable together with a roll of the adhesive tape band and a brake shoe arranged in sliding contact therewith. The movement restraining unit includes a pusher arranged to press the brake shoe and a pusher actuator for pressing the pusher against the brake shoe.
According to this preferred mode, the brake mechanism can apply an appropriate tension to the adhesive tape band running along the adhesive tape band path, and the movement restraining unit can urge the brake mechanism to restrain the movement of the adhesive tape band in sticking the double-coated adhesive tape piece to the web. Thus, the construction of the movement restraining unit can be simplified if the sticking device is provided with the brake mechanism.
Preferably, the sticking device of the present invention further comprises a control section for controlling the drive of the delivery section, the first and second drive sections, and the movement restraining unit.
According to this preferred mode, sticking of the double-coated adhesive tape piece to the web by means of the sticking device can be carried out automatically and securely.